Transcript Abnormal - ResourcdBlogs

Home Learning
For lesson 1
Definitions of Abnormal Behaviour:
Statistical Infrequency and Deviation
from Social Norms
Specification:
Describe the statistical infrequency and the ‘social
norms’ definition of abnormality.
Evaluate these definitions in terms of their suitability
as definitions of abnormality.
Definitions of abnormal behaviour
• Defining a person or behaviour as ‘abnormal’
implies something undesirable and requiring
change
• Therefore, we must be careful how we use the
term
• However, psychologists do need methods for
distinguishing ‘abnormal’ where a person
potentially requires some form of
intervention, from ‘normal’
4 ways of defining dysfunctional
behaviour
•
•
•
•
1) Deviation from social norms
2) Statistical Infrequency
3) Failure to function
4) deviation from ideal mental health
Statistical Infrequency
• Under this definition, a person’s trait, thinking
or behaviour is classified as abnormal if it is
rare or statistically unusual.
• With this definition it is necessary to be clear
about how rare a trait or behaviour needs to
be before we class it as abnormal
Mean IQ in the
population is 100pts.
frequency
The further from 100
you look, the fewer
people you find
70
100
IQ Scores
130
www.psychlotron.org.uk
Statistical Infrequency
www.psychlotron.org.uk
Statistical Infrequency
A very small subset of
the population (<2.2%)
have an IQ below 70pts.
Such people are
statistically rare. We
regard them as having
abnormally low IQs
frequency
Two Standard deviations
One Standard
deviation
70
100
IQ Scores
130
SUMMARY: Statistical Infrequency:
• Requires a behaviour/trait to be quantifiable
• Requires a behaviour/trait to be normally
distributed within the population- bell curve on a
graph.
• The mean for the behaviour/trait can be
calculated along with standard deviations away
from this point
• Abnormal behaviours/traits are those which fall
into the top and bottom 2.5%: typically more
than 2 standard deviations away from the mean.
Deviation from Social Norms
• Every society has accepted standards of
behaviour, these are sometimes written as
part of the law.
• Others are implicit : they are generally
accepted but not legally binding
• E.g. not standing too close to someone
when they are talking.
• Social norms allow for the regulation of
normal behaviour.
• One approach to defining abnormal
behaviour is to consider deviations from
the social norm as an indicator of
dysfunctional behaviour.
Deviation from Social Norms
• Examples of social norms include
1.
2.
3.
4.
5.
6.
7.
Being polite
Opening doors for people
Not hearing voices
Not washing your hands 50 times a day
Queuing in shops
Not standing too close to people when talking
Wear clothes when walking around outside
• These are just a few example. If someone was not
acting within these social norms, their behaviour
would be defined as abnormal.